Over the last 50 years, obesity has been increasing at an alarming rate and is now recognized by leading government health authorities, such as the Centers for Disease Control (CDC) and National Institutes of Health (NIH), as a disease. In the United States alone, obesity affects more than 60 million individuals and is considered the second leading cause of preventable death. Worldwide, approximately 1.6 billion adults are overweight, and it is estimated that obesity affects at least 400 million adults.
Obesity is caused by a wide range of factors including genetics, metabolic disorders, physical and psychological issues, lifestyle, and poor nutrition. Millions of obese and overweight individuals first turn to diet, fitness and medication to lose weight; however, these efforts alone are often not enough to keep weight at a level that is optimal for good health. Surgery is another increasingly viable alternative for those with a Body Mass Index (BMI) of greater than 40. In fact, the number of bariatric surgeries in the United States was estimated to be about 400,000 in 2010.
Examples of surgical methods and devices used to treat obesity include the LAP-BAND® (Allergan Medical of Irvine, Calif.) gastric band and the LAP-BAND AP® (Allergan). However, surgery might not be an option for every obese individual; for certain patients, non-surgical therapies or minimal-surgery options are more effective or appropriate.
In the early 1980s, physicians began to experiment with the placement of intragastric balloons to reduce the size of the stomach reservoir, and consequently its capacity for food. Once deployed in the stomach, the balloon helps to trigger a sensation of fullness and a decreased feeling of hunger. These devices are designed to provide therapy for moderately obese individuals who need to shed pounds in preparation for surgery, or as part of a dietary or behavioral modification program. These balloons are typically cylindrical or pear-shaped, generally range in size from 200-500 ml or more, are made of an elastomer such as silicone, polyurethane, or latex, and are filled with air, an inert gas, water, or saline.
One such inflatable intragastric balloon is described in U.S. Pat. No. 5,084,061 and is commercially available as the BioEnterics Intragastric Balloon System (“BIB System,” sold under the trademark ORBERA). The BIB System comprises a silicone elastomer intragastric balloon that is inserted into the stomach and filled with fluid. Conventionally, the balloons are placed in the stomach in an empty or deflated state and thereafter filled (fully or partially) with a suitable fluid. The balloon occupies space in the stomach, thereby leaving less room available for food and creating a feeling of satiety for the patient. Placement of the intragastric balloon is non-surgical, trans-oral, usually requiring no more than 20-30 minutes. The procedure is performed gastroscopically in an outpatient setting, typically using local anesthesia and sedation. Placement of such balloons is temporary, and such balloons are typically removed after about six months. Removing the balloon requires deflation by puncturing with a gastroscopic instrument, and either aspirating the contents of the balloon and removing it, or allowing the fluid to pass into the patient's stomach. Clinical results with these devices show that for many obese patients, the intragastric balloons significantly help to control appetite and accomplish weight loss.
Some attempted solutions for weight loss by placing devices in the stomach result in unintended consequences. For instance, some devices tend to cause food and liquid to back up in the stomach, leading to symptoms of gastroesophageal reflux disease (GERD), a condition in which the stomach contents (food or liquid) leak backwards from the stomach into the esophagus. Also, the stomach acclimates to some gastric implant devices, leading to an expansion of stomach volume and consequent reduction in the efficacy of the device.
Therefore, despite many advances in the design of intragastric obesity treatment implants, there remains a need for improved devices that can be implanted for longer periods than before or otherwise address certain drawbacks of intragastric balloons and other such implants.